Vapor trap



May 5, 1953 W. s. Gol-'F 2,637,335

VAPOR TRAP Filed Nov. 8, 1949 3 Sheets-Sheet l INVENTOR William S Goff ATTORNEYS May 5, 1953 W. s. Gor-'F 2,637,335

VAPOR TRAP Filed Nov. 8, 1949 5 sheetssheet 2 40) uNvENToR if Wiliam S, Goff 45 f Y' i g/y' BY www@ ATTORNEYS May 5, 1953 W. 5 GOFF 2,637,335

INVENTOR W'llam 5. Goff ATTORNEYS Patented May 5, 1953 UNITED STATES PATE 'l1 FFICE Clark Manufacturing Company,

#Eleveland,

Olii-o, a corporation of Ghia Application November 8, 1949, Serial No. 126,227

(Cl. BTL-185) 26 claims. i

This invention relates to fluid traps suchas steam traps, and particularly to valve mechanism of both the submersible and non-submerging float types for' opening and closing a discharge oriiice.

Heretoiore a number of problems involved in the construction and mode oi' operation of: valve mechanisms for vapor traps, have been only par;- tially solved by eilecting, compromises between a number ofl desirable conditions; As a result, most of these desirable conditions have not beeny met in an entirely satisfactory manner'. The most important of` these desirable conditions are? (u) Positive actuation of the discharge' valve under all conditions encountered in service? (o) High sensitivity' to changesin the conditions calling for opening and closing of the discharge valve;

(c) Efficient gases;

(d) Operability of' a given trap over a wide range of fluid pressures'andcondensate'discharge. rates;

(e) Adaptability'o-f a given trap size and design to still wider rang-es of operating pressures and condensate discharge rates with minimum changing of parts;

(f) Ruggedness and durability in service;

("g) 'Compactness of the valve actuating mechanism;

Ui)- Simplicity and economy of manufacture' and repair.

The difficulties encountered insatisfying all] of' these conditions as f'ully-y asvv possible' are principally` due to. friction in the mechanism; tothe* large initial force required to crack the valve open against the internal pressure inthe trap; and to the amplitude oi'valve travel required duringl the remainder of the opening operationtopermit discharge of condensate through the dischargeorii'ce with minirrrum'- tlirottling and turbulence.

Ameasurez of successJin overcoming these d-iilicuities` has been. achieved in the prior art by' employing two succe'ssively'operativef fulcrums orrtne float-actuated valve lever. This. hasr involved pivoting` the, lever. about a. first'.orfizuirvr1`ar-y"ful-y crum; disposedA close to: the valve untilthe valve is cracked. open sufciently tol overcome. the: great initial, resistance; toits opening; movement,u and then pivoting the lever about ai secondary' fulcruni iurther; removed from` the'y valve? to obtain. the desired total amplitude of, valvetravel`- to.- its fully open position.4

Anl application. of, the dual. fulcrum principle isV shown. in Uf.r Si Patent No. 29,041,953. to.y Kaye. The mechanism of this patent is of a relatively removall of n'on-condensable simple character. However, the geometry' of the lever system isl such that either the valve'- travel while the primary fulcrum is operati-Ve is too'y smal-l to carry the valve out of the region in which a large opening force is required, or the initial mechanica-l advantage is too small to eiiect reliable operation. Fory this mechanism` to be reliably operative over' a wide range of steam oressuresv for opening a large valve capable of handling large condensate discharge rates, anx undesira'bly large housing containing a long.A valveA lever is required.

Thepresent invention is animprovement over these and other prior' art devices employing' the dual ulcrum, or differential lever, principle:

A main object of the invention isV to provide" a dualfulcrum actuating-` mechanism for moving a large spherical valve element between operiy and closed positions in pressure systems without enlarging the lever and trap-housingbei vond sizes formerly operative only at lower pressures and lower rates' oil condensate discharge;

Another object of the invention is to providesuchy a dual fulcrumactuating mechanism that is small and compact', yet capable of functioningv efliciently' over a Wide range of vapor pressures' and condensate discharge`v ratesf.

nother and more' specific object oi*V theiinvenetionv is to-provide-a dual fulcrumactuatingfmech anism which wil-ll delay the' valve) opening operabtionuntil the float has moved a' substantial distance and: has developed close to its maximumpower.

Another specificl object ofthe inventionI isI to' provide an improved variable ven-t fory an' in-f verted bucket type of valve actuatingy float for' increasing the power derivableI from' a1 oa-t olav given si'zeduring its downward movement,` there-v by' more completely achieving the aboveenumer@ ated desirable conditions.

Other objects andi advant'ages'l of the invert-- tion will become apparent froml the followingl description of illustrative embodiments thereof, taken in! conjunction with thef accompanyin'gy drawings in'4 which:v

Figure l isl a side eleva-tion ofv a. vapor trap-em'- bodying the invention,VX a portion of theA housing being broken away to show the valve mechanism; with the valve fullyclosed andl the inverted bucket in its fully raised position;l

Figure 2Y is a fragmentary vertical sectionon an; enlarged scale showing` the valve stillin itSzully closed positionr after theI buckethasstarted its downward travel; l

Figure 3 isa fraugrnentaryl verticalvsectiom similar to Fig. 2', Vshowing the valve, the valve lever,

3 and a portion of the bucket after they have moved to positions for first cracking the valve open;

Figure 4 is another fragmentary vertical section similar to Fig. 2, showing the valve and valve lever just as the second of the two fulcrums becomes operative during the opening of the valve, a fourth position with the valve in a substantially fully open condition being shown in phantom outline;

Figure 5 is a fragmentary vertical section on an enlarged scale showing the connection between the bucket and the valve lever that provides a variable vent for the bucket, the plane of the section being indicated by the line 5-5 in Fig. 3 but the variable vent being shown in its closed position;

Figure 6 is a bottom view of the bucket and illustrates details of the connection between the bucket and the valve lever;

Figure '7 is a fragmentary vertical section through the valve, the plane of the section being indicated by the line 'I-'i in Fig. 3;

Figure 8 is another fragmentary vertical section through the valve, the plane of the section being the same as in Fig. 7 but the valve lever being shown in a position for removing it from y the associated parts of the valve mechanism;

Figure 9 is a perspective view of a yoke in which the valve lever is mounted and which provides I,

bearing surfaces for fulcrum edges on the Valve lever;

Figure 10 is another fragmentary vertical section similar to Fig. 2, but showing how positive closing of the valve is assured under all conditions of operation; and

Figure 1l is a vertical section -through the center of a modified form of the invention in which the invention is applied to a vapor trap of the open bucket type.

Referring to Figs. 1 to 10, the invention is a shown as applied to a steam trap having a cupshaped body or housing I including a separable cover member 2 secured to the body I by means of bolts 3 to provide a condensate chamber 4.

The chamber 4, which is normally full of liquid,

is provided with a steam and condensate inlet 5 at the bottom thereof, and the cover 2 denes an opening 6 through which condensate and accumulated gases may be discharged.

In side the chamber 4, the cover member 2 is y provided with a counterbore 'I concentric with the discharge opening 6 and of greater diameter for receiving the upper end of a valve port housing 8. A gasket 3 is disposed between the upper end of the valve port housing 8 and the upper end of the counterbore "I, and an outwardly flanged orifice sleeve I0, defining a circular valve seat II, is inserted into the valve port housing with a press nt. The valve port housing 8 is secured to the cover member 2 by means of a plurality of bolts I2 (Fig. 7).

A yoke I5, having a pair of downwardly extending arms I6 and I'I and an aperture I8 through the base thereof, is secured to the valve port housing 6 with the orifice sleeve I0 passing through the aperture I8, the yoke being firmly held in place by a flange on the orifice sleeve.

One of the arms I6 of the yoke I5 has an irregularly shaped aperture therethrough, and the other arm Il has a similar aperture 2! therethrough, a slot 22 being cut from the lower end of the arm I'I into the aperture 2I for a purpose hereinafter described.

A movable valve element 23, having a spheri- 'mary 4 cal surface 24, is normally seated against the valve seat I I when closed, being held against the valve seat in a manner hereinafter described. A valve actuating lever 25, having a pair of laterally extending trunnions 26 and 2l, is mounted with the trunnions respectively projecting outwardly into the apertures 20 and 2I in the arms of the yoke I5. The valve element 23 is provided with a cylindrical extension or stem 28 that projects through an aperture in the lever 25, and the valve element is firmly secured to the lever by any suitable means, such as deformable lock nut 29, or the like.

The generally horizontal upper edges of the apertures 20 and 2| in the arms of the yoke I5 are similarly formed so that each provides two bearing surfaces 30 and 3| for fulcrum edges formed on the trunnions of the valve actuating lever 25. As most clearly shown in Figs. 2 to 4, one edge of each of the trunnions 25 and 21 is upwardly turned to provide a pair of transversely extending and aligned fulcrum edges 32. The adjacent terminal edge of the valve lever 25 constitutes a second pair of aligned fulcrum edges 33 which extend transversely of the lever 25. In the course of movement of the valve lever 25, as hereinafter described, the primary fulcrum edges 32 respectively engage the two bearing surfaces 30 and cause the valve element 23 to be moved away from the valve seat I I. As the valve lever is further rotated in the same direction, the secondary fulcrum edges 33 respectively engage the two bearing surfaces 3I; and the primary fulcrum edges 32 are respectively disengaged from the bearing surfaces 30 as the lever is rotated on the secondary fulcrum edges to move the valve element further away from the valve seat.

As is most clearly shown in Fig. 3, the primary fulcrum edges 32 lie in a diametrical plane A-A of the sperical valve surface 24. As is illustrated by the sequence of positions shown in Figs. 2 to 4, this diametrical plane becomes substantially parallel to the valve seat II as the primary fulcrum edges 32 first engage their bearing surfaces 30 for initially moving the valve element away from the valve seat. This parallel relationship between the two planes theoretically should exist when the lever has pivoted through half of the angle through which it is supported on the prifulcrums. However, the relationship shown approximates this ideal condition sufliciently closely for all practical purposes and is most convenient to construct.

With this relationship between the primary n fulcrum edges 32 and the spherical surface 24 of the valve element, the initial direction of movement of the spherical center of the valve element is in a direction normal to the plane of the valve seat, thus effecting substantially the maximum effective opening of the valve for a given angle of rotation of the valve lever. This relationship also insures that the downward direction pull of the bucket on the lever 25 will be approximately normal to the lever arm at this time when the most effective application of that pull is needed.

The primary fulcrum edges 32 are preferably located on a line closer to the center of the spherical valve surface 24 than the spherical surface itself (i. e. on a line that passes between a portion of the spherical surface and its center) in order to obtain suifcient mechanical advantage from the lever to overcome the high re- 1 sistance to initial movement of the valve element awayifrom thevalveseat.itherebyfpermittingthe' escape ofi accumulated'- gasesi and. condensate" through 1 thef` orificei-L atarprogressivem-f increasing rate,xtheipre'ssur`e diierencefonthelfhigh and low-v pressure surfaces of. the valve?element?isI reducedv inl accordance with; the ldiininishingl fluid velocityT over'th'enlow pressure valve surfacaandalconstantly" diminishing.k fbrceiisreouiredi toty continueL the opening. nim/ementv ofstheavaiveelementi Itis desirableth'at tlieiva'lve element-bei moved@ fr'ori'i"l its fully closed position t`o"=its fully open?. position Lwith a Lrhin'im'um' angolari rotation dfi the' valve lever4 25,- and?` a Y' substantial@ increa'sei in" then' movement of l the valve element'perl degree oia1'1-Jv gl'il'aiA t'iaVel of thelever? 'eslltswhen? the soci#y ondaryfflcrum edgesfaioontacttlieibearing "sur`H faces 3 II to A provide a longer? lever? ar-in between thepoint-ofrotation of th'efvalvelI leverf and thel centerof the valveelem'enti-- This shiftingof-thei center? of' rotation of the valve' levert" accorn'e panied, of course'g byaf-red'iictionin'th'e meoh'an'# ical advantage 'off the` lever; .which is permissible 1 afterthe resultantl force" urging? the valve' ele@ ment toward the valve" stati" has also b'een'-- substantialli'r" reduced? as explained above.

The oppositeendL off the valve I lever 25 fromu the secondary filler-urn edgesv 33A is; defrrned` to provide a generally cylindrical socket 35" to which aniv inver-ted' bucket is"y pivotally" attached by means of` a`- connecting devicel 3BE The connect-v ingdevioec-eoinprisesa spindlerhavingf aherni-f spherical upper end' 3ft;v a cylindrical" neck 38* off reduced.v diameter,` and'v an" enlarged'y portion Se which" is1 rounded ati't's lower edge?l and? termi-1 nates'y in at stemt M having" al circumferential groovel f adj acentits'flower end The socketendioff the lever 25sis bifurcatedl to'- provide"A alon-- ditudinally' extending slot-P42y that? accommodates" thel' neck" 3'8' offl the" connecting device with4 the' hemispherical upper endl thereof` disposed Withe in' thel socketl 35. The connector isV thus sus-f pen'fledrv from the" socket 35 of the* lever' 2`5 ina manner permitting" 'freeV swinging movement of the' connecting device about ani axis parallel to the" cylindrical axisr of the'soclet'.

The bucket" 415' comprises" a" cylindricall shell having an open lowerv end:v an'd a closed topf- AS that" is preferably' domelshapedl- The!F topj 416i off the bucket has a circular` depressionL 4T formedt therein and. an aperture 418V through' the bottom of the"depression The aperture" 4:8" is adapted` to loosely' receive the stem" 4 oT the connector 3'6 5 and' thesu'rface contourof 'the' depression 4T con'` forms to the" rounded lower edge surface of' the' connector portion 39t-A sovthatf an'effective# gas' seal isproduce'd when'the twosurfacesar'e rmlyengaged;

yieldable"member,v such asa thin' leaf' springr 1Q-that; is n'orniall'x'rr bowed from e'nd" to" end" as shown inY Fig. l0, i`s disposed' inside the" bucket; andV44 the stem" d'of'the connector proj ectsth'rough an" a'perturei'n th'ecenterof the spring. generally' U-shapeol bracket 5`0is disposed to strati"-vr dle' the i spring 49 withyv` its' legsiupturned'td engage tlietopllt of th'elbuclzetL and" lim'itupwarcll move"- ment of the connector 35i The" stem" 40 of the.` connector" also projects; through an apertuneh in the center'of'the bracket .ill;y and av deformable lock nut 5|*- eng'ages the groove 41`- of the stern of the connector for' preventing downward movement of* the" spring.1 and' the* bracket with respect tofthe'connectcr.v Thus, the ends of? the springv- 49' bear upward-ly againstl thel top" ofi` the'v` bucket' and* urgeL the* connector downwardly with re spectto thebucketand into" seating engagement si" withil thefsurfacei' of: the? depressioni 411. Upward; movement' of the connector,` withi rf'zspjeci'f to ther bucket".` is. yieldingly resistedi byftt'1e` spring and: positively limited bythebracketm asish'owniine- Fig; 5. The stiffness of the spring ist selected! tha'tzt11e.`r Weight!A of the` bucket; when? suspended in" theli'quid" inlthe trap l and substantially filled; Withthefliquid',.ismore than sunicient totstraight;.-d en the:` spring.' and. hold. thefpartsfinl the; relative:

F positions shown in Figs; 2 and.' 31 When' the? dow-nwardlpull of lthe vbucket'fis;veryfsmall diie-itc:` theacoumulation of. vapor therein, however;` thea. spring. should hold l the? connector: in4 seating: err-ff gagennent4 with: the 1. surface ofi the; depression as@ shownin; Figs.V 1i, 5l andi 1ct."y and' further: deze scribed;hereinafter.'v

The'` aperture 48 through' the@topofitheibucliet: issubstantially greater in' diameterfthan. thefdie ameterff ofi the stem llo'f.' the connector soif as tot` providel anauxiliary' vent" of) considerable? crossi I sectional area"y for exhausting? vapor" from the?y bucket whenthe l' connector` is raisediwith. respect'` to' the bucket; When the' connector is' seatedinl the' depression' 4'l` in theA topk ofA thebuck'et, this'r auxiliary vent' is closed; A smaller ventlopening,

52 in the top of'- the' bucketvremains,openiatiall times',..however,' in accordance with conventional practice;V The weight of the bucket? may besad justed to' balance the mechanismtby mounting: a steel ring 5d ofappropriate'. size. insider: therl bucket" adjacent theflower endl thereof.P

Theleaf spring L38,l restraining'opening ofxtlie auxiliary vent 45; also serves@ to restrain. the bucket from swinging' from` side. to side aboutfI the connectort andcauses-the bucketand connector to swing together. as aA unit? about; the;` socket 35.

When assembling the valve* actuatingy mech--l anism' contained Within' the chamber -fthe valve` `lever 25i with the valve element 23 secured there= to, held in'. vertical alignment withv the slot 22 inthe yoke' arin'- l1 and ih the laterally'oit-A center positonf with respect tothe armsE Ilfan'dt I' illustrated in phantomoutline iii-Fig; 8'.-` The? lever 25 is'then` moved vertically into theposi'= tionshown' in solid lines in Fig. 8, and thenfhoriw zontally to the leit'to move the' trunnion 243'into"y theapertnre 20 in' the yoke arm I 6; The'free enct ofv the= lever 2`5 is" then rotated to bring-'thef valve element 23 into position toclos'e'-thevalve'scelti` lil?.

vWhen initially installing the trap in vapor syse, tern, the trap-is preferably primed soA that the chamber i is full of liquid. When the trap-cover-4 2 is put in place with the bucket andvalve mechanism atttached thereto, the bucket; will drop toi the-bottom of the trap', andlthevalve mechanism-` Will assume the position illustrated with. solid." lines in Fig. 10; When the vapor system is turned?. on and vapor begins to bubble through the inleti: 5; the vapor accumulates in the' bucket at a' faster ratefthani it can escape throughlth'esmallvent 525, thus causing the bucket to'l become buoyantf and? rise to theitoplof chamber 4', wlerevitx comesltoli' rest as shown in Fig.' l` with the'zauxiliar-yfvente@ closed.

vali/clever' are` limited. by the lower edges oi" tle:v

apertures 2'and 2l upon whichtthetrunnionsf 2.5i andfl respectively rest. The lower: edgeofeacii L'of the-apertures 2@ and 2T is shaped? tofprovide trunnion supporting surfaces at two diierent levels. The uppermost of these surfaces 53 is adapted to support the adjacent end of the lever 25 during upward movement of the bucket, and the lever trunnions 25 and 2l pivot on these surfaces to raise the valve element 23 into seating engagement with the valve seat II. Thus, when vapor hasbubbled into the trap in suicient quantity to raise the bucket, the valve will close before the vapor pressure has risen to a point sufficient to blow through the open exhaust valve. When the pressure in the vapor system has reached its normal operating range, this pressure alone is sufricient to hold the valve element against the valve seatand support the weight of the valve element and the adjacent end of the lever. Upward movement of the bucket and upward swinging of the valve lever are limited by the valve element bea-ring against its seat and by the trunnions 26 and 21 bearing in the opposite direction against the supporting surfaces 53, as shown in phantom outline in Fig. 10. This is the relationship between the various parts of the mechanism that exists each time the valve is completely closed during normal operation and is the same relationship illustrated on a smaller scale in Fig. l.

To meet different conditions of operating pressure and volume of condensate that may be handled within the limits imposed by the size of the trap housing, only the valve element 23 and the orice sleeve I need be changed. By appropriately proportioning the dimensions of the different sizes of valve elements and orice sleeves, the above described relationship between the center of the spherical surface of each valve element and the position of the primary fulcrums may be maintained. The ready removability of the valve lever from the bracket I in which it is supported and the simple manner in which the valve element is secured to the valve lever make the substitution of different sizes of valve elements a simple operation. The substitution of different sizes of orifice sleeves is obviously equally simple, and the entire operation may be quickly performed. Thus, a minimum number of replacement parts need be purchased for converting a trap to operate over different pressure ranges. The adaptability of a given trap for operation over different pressure ranges by merely substituting two easily exchangeable parts also keepsvto a minimum the number of different trap sizes that must be manufactured and stocked by the trap supplier.

The cycle of operation of this form of trap will be described as applied to the elimination of condensate and accumulated gases from a steam system, starting with the bucket 135 in its uppermost position and. with the valve element 23 closing the discharge orifice I I, as shown in Fig. l. The chamber 4 is always substantially full of water, but the water level inside the float varies over a considerable range. Under the conditions illustrated in Fig. l, the water level inside the bucket may be approximately at the level indicated by the line B-B, the space above the water level inside the bucket being occupied by steam and accumulated gases. At this point in the cycle, the bucket is in its most buoyant condition and bears upwardly against the connector 36 holding the connector portion 39 upwardly against the bottom of the lever socket 35. rOnly the small vent 52 is openand the escape of gases from the bucket through this vent is relatively slow. At this stage, all of the fulcrum edges are spaced from their bearing surfaces, a condition which 8 remains unchanged during opening of the auxiliary vent 48, as most clearly shown in Fig. 1.

In due course, by reason of the escape of gases from the small vent 5I and the condensation of steam above the water level in the bucket, the water level rises inside the bucket, causing it to lose buoyancy and start to sink. The first small downward movement of the bucket takes up the lost motion slack between the connector 36 and the socket 35 of the valve lever, without moving the valve lever', until the connecting device is suspended from the socket 35 by the hemispherical portion 3l and the bucket is suspended from and partially supported by the connector. This opens the auxiliary bucket vent to the maximum effective cross-section determined by the size of the aperture 48, thus allowing a more rapid escape of steam and gases through the vent and rapid reduction of the buoyancy of the bucket. Up to this point, movement of the valve lever is restrained by friction between the valve element and valve seat. The positions of the bucket and connector at this stage are also shown in Fig. 2.

After the loss of buoyancy of the bucket has increased its downward pull on the lever 25 to a point sufficient to overcome the friction between the valve element 23 and its seat I I the valve element rotates on its seat in a counter-clockwise direction as viewed in Fig. 2. This rotation brings the primary fulcrum edges 32 into contact with the bearing surfaces 30 as shown in Fig. 3, whereupon further downward movement of the bucket causes the lever to pivot on the fulcrum edges 32 for initially moving the valve element substantially vertically away from its seat. By the time this initial cracking of the valve occurs, the bucket has had an opportunity to vent most of the gases contained therein through the small vent 52 and auxiliary vent 48 and has attained close to its maximum power. The downward pull of the bucket for pivoting the lever about the primary fulcrum edges 32 for initially cracking the valve open is thus greatly increased compared to the downward pull at the beginning of the cycle. In traps where the initial movement of the bucket is opposed by the full force required to crack the valve open, either a longer lever or a larger bucket, or both, are required under given conditions of operation.

When downward movement of the bucket has pivoted the valve lever about the primary fulcrum edges 32 to the position shown in Fig. 4, the secondary fulcrum edges 33 contact their bearing surfaces 3|. Further downward movement of the bucket and rotation of the valve lever then causes the lever to pivot about the secondary fulcrum edges 33 until the bucket contacts the bottom of the trap housing, at which point the valve is fully open. This position of the lever is illustrated in phantom outline in Fig. 4.

When the valve lever rst cracks the valve open, the water and accumulated gases in the chamber 4 begin to ow out through the orifice II, and this reduces the pressure differential between the high and low pressure sides of the valve element. However, due to the velocity effect of the water and gases passing through the valve orice while only partially open, the valve element maintains substantially the same high resistance to movement away from its seat during a substantial portion of the movement of the valve lever on the primary fulcrum edges. By the time the secondary fulcrum edges contact their supporting surfaces 3|, this velocity effect is greatly reduced, and completion of the valve opening .movementrof i the .lever .reguiresa constantly .diminishing downwardpull bythe bucket. -Accordingly, .the last `stage of the opening movement is reliably', carried tout in spite. of thel reduced` mechanical advantage 'resulting fromwshiiting the axis ofrotation fromtheprimary to the -secondfaryvfulcrum edges. AThis last stageof opening :movement of the :valve element 23 is also opposed bya `constantly, diminislfiing-` diiereritialy between vits high vand0W-.pressure sidesandlitt1e or no ,downvvardpull by the bucketis necessary to hold the valve in its fully openedpositio-n. rAs va result,

A,the socket 35 of the `valve lever Willggenerally come to rest upon the top of the :cylindrical por- ;.tion 39 Iof the bucketconnector, as .shown-in `-Fig. 10, thoughthe.secondaryffulcrumedges 33 .mayremain in contact With their bearing sur- .-,f-acesi.

.As `Water and accumulated gases .ow `out through the openorifice i, i some .additionalgases flowifrom .the;in1et ..5 yinto .the .inverted bucket. jHoWevensinoe `the gases .above'the Water" level Ain thebucket are being exhausted at a relatively ,rapid rate duringdownward .movement of the bucketsinking of the bucketto the bottom of the trap is assured. When the bucket has come to a--stop at the bottom of the trap, however,-the auxiliary'vent 48 closes'and further escape 0f -gasesffrom thebucket can take place only at relatively -slow rate through the small vent 52.

'When the flow-of: condensate through the trap thas substantially" reduced the distance tovwhi'ch .liquidis backed up' inthe'inlet lineli, steam will begin to? bubble -intotthe'trap through the inlet'5 at c an increasediratexfand fzwillwcollecti in theiup- 1 n per 'parteci the -tbueketfmuchffaster than it vcan :be discharged 3 through the small' vent 52.

AS i a result, the-Iwater level in the .bucket is rapidly 11 forced; `downivardly.by accumulation of jgases in the upper part of the bucket, and the bucket rapidlyregains ,buoyancy .and begins'. to rise and .return thevalve element.A to `its closed position.

At .the beginning ofthe valve-closing operation the l,pressure .differential .between the high .and Vloiv.pressure sides of the valve. elementI-Ylay y0r mayI not be `suiiicient to hold the.. secondary ful- .,erurnedges` 3,3, against their bearing surfaces I Thus, 4the closing movement of .the valve flever may .initially involve either xpivotal ,movement .,.aboutthesecondary fulcrum .edges .orpivyetal ,movement of the trunnions2t` and?! `.on the surfaces `i3,..describedabove. In any event, as.the" blicliet,risesand causes the valve er to rotateiine,clockwisedirectionasviewed Wigsilto j4the.valve element.Willlberaised into contact with the valve sea-t, vat ,Whichnpoint the ,:pressure,diierentialbetween the high vandlow pressure sides othevalve element Will insure centering of the valveelement on its seat and tight closing of the valve.

During the-final movement of the valve element y tovvardthe valve seat, thepriinary fulcrum edges will normally be in engagement with their supportingsurfaces and the variousypartsof the mechanism will `again reach ,the .condition z shownlinig.' 3, except thatthe auxiliary ventfli will be oloseddueto thelbuoyancy of thebucket. At this point.' ,the` .buoyancy .of ...the bucket. is. suincientlto continue thecloolzwise `rotation of ,the

lever from `the position vshovvn in Fig. 3 to i the hposition shown in Figs. A1 .and c,byiotating.the

valve ,.elenient .upon its seat, thusA returning the mechanism to .thestarting 4position .shown in Fig. .l ,completing the ,cycleJ of operation.

Some of `,the ,detailsof the cycle .of operation ',-dcscr-ibed -abovecannot .readily be visually observed, even While using a transparent glass housing Vl because of the rapid movement of the valve mechanism. Thefentireccyole of operation maybeicompleted ina fraction of a second or may require .several seconds, but any substantial :amount of time during'whichthe parts remain stationary for-.easy'observation occurs either with :the bucket 'atrest in its uppermost position 0r at rest in yits lowermost position. As -a result, some of the details of the cycle of operation described above yare vsomewhat conjectural under some conditions ofloperation. However, the improved :over-all operation vresulting from the V.critical features -cf ,theinvention (suchuas the vvalve and iulcrumrelationship, the variable vent vandlost motienconnectonand the delayA of the lopeningfofthevalve until-thefbucket has ac- A quired closeto: itsinaximum power) can .only be explainedif the cycleof operation takes place substantially as described in all of its essential etails. y.Regardless,of .the accuracy of any theory Jof operation of the device, thel advantagesoi the invention ,are evidenced lby substantially improved overall operation, endl do not wish `the invention to be limited by any particulartheory .of operation beyond what is required by, therap- .pended claims.

A .valuable characteristic` of the valve mecha- -nism .described above is` its suitability-for use in traps other than those ofl the inverted bucket type :such `as the'open or upright bucket and closed .lioat types. is illustratedin Fig. l11 byxits Eapplication to an open bucket type of trap. yIn Fig. il, parts identi- The adaptability of the vmechanism cal or substantially identical lWiththose inthe ,trap ,of Figs. .l to l0 vare identifiedby thesame Areferencecharacters--einployed in Figs. `l to l0.

vSteierring tti-Fig. .11, the'tra-p comprisesacupshaped:bodyv orrhousing t anda separable cover mem-berF Si' .Y that `are generally similar `to .those shown in Fig.l, and-aspacing element therebetween. The spacing element @d includes'apar- Atition @il that divides the interiorof the housing `intoya lower condensatecollecting clfiamber t5 an upper chamber 6l containing the valve .mechanism proper. The housing-6 l cover member 52,l and spacing 4element t3' are separated vby :gaskets and-69, and the three partsof the housing are iiirmly 4secured together at their vilanges in a wellknownmanner by suitable' bolts (not: shown).

VThe lower condensate chamber e@ provided tvithafStea-mfand condensate inlet 'H disposed in thefside vvallv of .thelspacing element 53,and the cover-member G12 :defines an opening-' through which condensate-isdischarged. Insidev the uppeichamber-lfthe covermember 52 is provided with `a ecunterbcre 'i concentric with the'idisolmlge-openingk 5. and -of greater diarneter'forv re- .ceivingthe-upperend ofra valve port housing il.

The valve port housing is mounted in the count-erbore i @inthe-cover member Q2-in the same .manner .as in the embodiment toi .the invention lshown in Figs.;1ito;10. .The valve port housing ilinFig. llfearries'avalv@ Seatvalveelement,

.valve lever, and associatedfeiinpoitng SBI'UCUHTS,

all of `which .are identical with the corresponding .parts ini-Figs. .l =gto '10. Further Adescription Vof these .parte is,f.therefore, not required.

A1-float 'i2a ofthe open buokettype isdisposed within .the lower eondensatechainber 65 and .comprises. a cup-.shaped upperportion ls-having a cup-shaped well M of substantially smaller ldi- .,:arneter extending .downwardly from the yupper 11 portion and centrally disposed with respect thereto.

A connecting device for attaching the oat to the valve lever 25 consists of a generally vertical disposed connecting rod 15 that passes through an aperture 16 in the partition G4. The rod 15 has a reduced neck portion 'Il adjacent its upper end and terminates in an enlarged hemispherical portion '18. The neck portion H nts in the slot 42 in the bifurcated end of the lever 25, and the hemispherical portion 18 is disposed within the lever socket 35. The lower end of the connecting rod 15 terminates in a threaded portion of reduced diameter that passes centrally through the bottom of the float well 'i4 and is secured thereto as by a nut 8| A suitable washer 32 and gasket 83 are preferably mounted on the threaded portion of the connecting rod 'i5 above the bottom of the oat well 'I4 for sealing the well against leakage where the connecting rod passes therethrough. 1

A tube 84 is threaded at its upper end into the aperture 16 in the partition 5d and surrounds the connecting rod 'l5 between the partition 64 and a point normally adjacent the bottom of the float well 14.

A Vent opening 86 is provided in a suitable location, such as in the partition 64, for maintaining substantially the same pressure in both the lower condensate chamber 86 and the upper chamber 11, and an appropriately shaped baille 81 is secured to, or formed integrally with, the partition 6G opposite the steam and condensate inlet 1| for directing condensate entering the inlet downwardly into the condensate chamber outside of the float 12.

Under normal operation, there is suiicient water in the condensate collecting chamber 65 to support the oat 12 in its uppermost position shown in Fig. ll. As additional condensate collects in the chamber 66, the water level rises therein and overflows into the iloat 12. When the level in the float 12 rises to the approximate height indicated by the arrow C in the Fig. 12, the float sinks and actuates the valve lever to open the discharge valve in substantially the manner previously described. By reason of the small size of the vent 86, the pressure tends to drop more rapidly in the upper chamber 61 than in the condensate chamber 65, and the water in the float is forced upwardly through the tube 84, lling the upper chamber 61 and discharging through the outlet 6 until the level in the lower chamber drops to the upper rim of the float and the level within the float approaches the lower end of the tube 84. Reduction of the quantity of liquid in the oat increases its buoyancy and, before the liquid level therein drops as far as the lower end of the tube 84, the float reaches its uppermost position again, closing the discharge valve in the process, and completing the cycle of operation.

From the foregoing description of the construction and mode of operation of two embodiments of my invention, it should be apparent that a trap has been provided that is more positive in its operation than the prior art devices. Also, the novel valve lever and its supporting structure permit the application of the general type of dual fulcrum arangement shown in the above mentioned Kaye patent to a downwardly opening valve, thereby increasing the space available in the housing for accommodating a float of maximum diameter.

The location of the primary fulcrum with respect to the valve seat increases the effective opening of the discharge valve obtainable from a given angular movement of the lever and from given lever arm proportions. This in turn permits the primary fulcrum to be located closer to the spherical center of the valve element, with the result that a greater valve opening force can be derived from a given total lever length and distance of oat or bucket travel. These combined effects materially reduce the Width and depth of the housing required to meet specific pressure and volume demands. The variable vent mechanism for the inverted bucket and the lost motion effect in the connector 36, together with the provision for rotating the valve element on its valve seat through a small angle before cracking the valve open, substantially increase the effective power obtainable from a bucket of a given diameter 'and contribute further to the ultimate objectives set forth herein.

The maximum pressure and volume capacities of a given mechanism, as a practical matter, are dependent upon the available space within the trap housing, and there are definite practical and economic limitations upon the trap sizes that may be employed in particular installations and upon the number of trap sizes that may be economically manufactured and stocked to meet the entire range of service demands. Accordingly, the above described advantages of my invention are of great pratical significance in raising the maximum limits and extending the range of pressure and volume capacities that can be attained with a single size of trap housing. As a result, the number of sizes of traps that must be stocked to meet all service conditions encountered in practice has been materially reduced.

Having described the invention in detail, I claim:

l. A fluid trap having a housing defining an outlet orifice, a valve seat surrounding said orice, a valve element having a spherical surface for engaging said seat to close said orice and for rotating on said seat to and from a normal orice closing position, a valve actuating lever attached to the valve element and mounted for oscillation to move the valve element in orifice opening and orifice closing directions, said lever being shaped to provide a pair of rocking fulcrum elements spaced Iapart generally longitudinally of the lever, structure fixed with respect to said oriiice and shaped to provide a cooperating pair of stationary fulcrum elements spaced apart generally longitudinally of the lever, said stationary fulcrum elements and said valve seat being arranged in a spacial relationship with said spherical surface and said rocking fulcrum elements such that said rocking fulcrum elements are spaced away from said stationary fulcrum elements when the valve element is in its normal orifice closing position and such that said rocking fulcrum elements successively engage said stationary fulcrum elements, respectively, to provide lever arms of different effective lengths as the lever is moved in an orifice opening direction for rst rocking the valve element on the valve seat and then moving the valve element away from the valve seat, and power means disposed in said housing for reciprocation along a path between predetermined limits, said power means being connected to said lever for oscillating the same to move said valve element in orifice opening and orifice closing directions, said v-alve element being in its normal orifice closing position ingesamt when 'sa-id `power fine-ans f is y:fat :one iof the limits Td-f its -:path o'fitraveL zwhereby :movement :of l the :power fmeans 'along said path :for effecting oriice openingzmovement :of the lever :first :causes the valve element .'-to rrotateion `its seat vfor engaging one-of 'said rockingfulcrumielements with :one of said stationaryfulcrum:elementsv and then :causes 4the lever 'to y'rock "on y-said:stationary" ful- 1 Crum l elements successively fors moving f the valve 7.element away "from its seat.

F2. iuid trap faccordingto :claim 1in 'which ".saidf structure :providingxsaid pair of "stationary flilcrum :elements y is -a :bifurcated bracketrrhaving Pits two legs straddling saidleverandshaped .,to "-forrn Aapair of fcooperating members on vopporsite 4sides ofl said lever that constitute one "of-said :stationary E"fulerurn elements *and :a "second `.pair Fo'ffcooperating membersfonfopposite sides offs-aid *lever that constitutetne 'other-of saidstationary flcrum'elements.

3. ."A'fuid' trap `aneording tto wclaim Nl in "which fsaid *structure providing saidtpair of stationary T'fiilcrurn "elements is fa' bifurcate'd i 'bracket having i its'ltwo legs 'straddling said lever rand shaped to form a pair of cooperating memberson'opposite isides Aof said lever that f constitute Yone of :2s-aid ffstationa'ry ifulcrurnelements'andasecond pair of .fcooperating lfmenibers t on Vopposite *sides `of :said lever'that constitute thev other 'of said stationary ifulcrumfelernents, 'and said levenhaving trunfrnions "extending laterally' thereof iny opposite A"difrections, sai'd i trunnions being shaped to form a lpair f cooperating members onf opposite -sidespf rsa-idleventnat constitute one of saidrocking 'Ifulcrum `elementsanil a 'second pair offcooperat- "F ing "members that "constitute the other of Asaid l"rocking"fulcrurn elements.

ff4."'-The device-offelaiml iii-Which the strucfiure providing'the 'pair of stationary' flcrurn eleifrnents Vcomprises `a "bifurcated l"bracket and the 4V"leverf is `4mounted 'betweenthe twofspaced legs vof Ethe bracket, the two" legsfof said bracket having *aligned apertures vtlneretlfiroug'n each 'of 'saidstati'onaryf'fulcrum' elements being 'definedv kloy aligned *portions o'ithe: edges of" said47 apertures, and :said #lever' having `trunnions extending' laterally thereof in opposite'directions vinto fsaid apertures-respectivelyland forming 'aligned portions of reach fsaid rocking fulcrum elements `for supporting tneu lever oni-said stationaryfu-lcrum elements.

v"5. "In a fluid trap-havingaliousing de'ning'an out-letorice,- afvalvefseat surrounding r-said oriffice;v a` valve element having a `splierioal surface for engaging said seat to'close said orifice,'a'valve :actuating lever attached to vtlie valve element, lstructure providingdisedprimary and secondary f' fulcrums upon `which the leversuccessively "rocks 'when `aotuat-edto move the 'valve'elernent yaway "from itsseatfsaid 'fulcru-rns' being spaced apart `'generally longitudinally 'of the lever to 'provide lever "arms of "di'ierent e'iective lengths, "and "power l'means adapted 'to move along "a V`path Iloetvveen predetermined 'limits for rocking the 'lever'about said primary and secondary iulcrurns successively Ito f'move the valve element -`from `said orieethefaxis 'of the primary iulcrum being disposed in aidi-ametric "planeof the sphericaisuriace of said valveelernent'andsaid plane vi'being substantially parallel to said Yseat 'at a stage 'during rockingfoithe'lever on the primary fulcrum.

E6. In a ."iiuidl trapfhavingia'lieusing defining a liquid" and' vaporireceivingfchamber. andA an foutlet orce that prorddesiianzinterior lvralveseat, an; valve element within :tire chamber Shaving a'-` E40 liquidita .spherical .'surfa'ceniormally engaging 'said seat, -a ivalveactuating lever ,attached :to :said valve ,ele- `frnentfandprovidingprimary and secondary ful- .'crum 'edges `thereon :spaced 1 apart longitudinally thereof, :structure -providing :fixed vfulczruin bearing Fsurfaces for said .fulcrurn edges, and power v:means :adapted :to reciprocate along a ,path rbetweentpredetermined limits for rocking .said lleverigon `said :primary fand secondary .fulcrum edges successively to Amove :the `:valve element away :from :said iseat, `the "axis of `the :primary :fulcrum Joeing disposed Vin :a diametric plane of .the spherical surface of isai'd :valve i element, and :said :plane ,being :substantially Yparallel t0 :said :seat atzca stageduring Arocking of `the valve .ele-

:ment enttnefprimary .fulcrurn '7. :In aiuidtraprhaving 'a housing defining: a liquid and `vapor vreeeiving "Chamberland -an outllet orice .that Yprovides,aniinterior valve .,seat, a valve element `within `the chamber having a ispherical :surface normally engaging .said seat, a Vvaive actuating ilever. atta'cl'red`r to said valve 1 ele- ;am'entsand `providing primary :andfsecondarygiulrum isedges titliereon spaced f. apart longitudinally hereof, structure providing 'Xed iulcrum bear- .zing surfaces .for said .'ulcrum .edges, `and :power :means adapted itornove along a path .between predeterinined limits :for :rocking '.said lever on :said tprimary 'and 1 secondary fulcrurn ledges .suc-

"30 lcessively :to :move 'the uvalve element :away l.from

. isa-idtseat, 4tlre 'faxis r (if the; primary iuloruini being zdi'sprose'd #a cdi'ainetric plane :ef Ttl're .spherical Ssurface of .sai'd valve element and fat `a dista-nce from Lthe spherical center Tof rsaid surface ,less

35 util-aniitssradiusfofecurvature; and fsaid' plan-e being substantially zpanall'el to :said :seat 'at a stage i:during rocking of? the ilever vnnftlie rprimary ...ful-

tcruin` 1:13. ffn'" uid'itrapxl'iavingfa housing dening; a vapor reoeivingichaznlaer 'and anoutlet 'Lor'ree:tnatprovides,afcircular,interionvalveseaty ra 7valve i-elem'ent 'within vthe icliarnser ,having a aplierical isurlacemo'rmally fiengaging said seat .Tier :closing said orifice, a `:valve actuating lever :attached :to said .valve element @and 'providing sprinrary iandseoondaryilpairs offaligned Ifulorurn eedges thereon, :the fulerumiedges of eaclrpair extending transversely of the lever beyond oppo- 'isitegsides of saidvalve .'elernent,tliel pair ofsec- 150 endaryiulcrunr edges-:beingfspacedl from thegpair of primary fulerumredgeslongitudinally of .said .leverfgand i' at ra greater distance .from the :valve :el'enrent, structure '1.tl'iat: isi-fixed with Vrespect dto @said j:seat providing :hearing -isurfaces iforfsaid :155 pairs of fulcrum edges and power means adapted "to move along :a :path between predetermined limits :for rocking vtne lever about said primary :secondary ulcrum fedges .successively .to rinove "the" valve .element yaway Afrom it" seat, ithe v60 pair .of yprimary fiulcruin edgesbeing operative w65 ftiallyz parallel Lto'- said seat sataistagextduring 'the timetheipairif primaryzfulcrumfedges engages its hearing: surfaces.

ln auiditrapnavingfa housing defining uid land vaporreceiving chan'iber and an outlet orifice that provides circular interior ilvalve '.seat, a '1 valve r element' within th e chamber il'raving `a spherical i* surface normally engaging ffsaidi seataa valve" actuating lever attached 'to said 4fvalve:elementfandtprovidingltwo4 pairs of fulcrum ledges tlfiereon, fthe `fulcrvun' edges of -eaehff pair being aligned and extending laterally beyond opposite sides of said valve element and the pairs of fulorum edges being spaced longitudinally of said lever, structure that is iixed with respect to said seat providing bearing surfaces for said fulcrum edges, and power means adapted to move along a path between predetermined limits for rocking said lever on said pairs of fulcrum edges successively for moving the valve element away from its seat, the pair of said fulcrum edges about which said lever first rocks being disposed in a diametric plane of the spherical surface of said valve and on a line at a distance from the spherical center of said surface less than its radius of curvature, and said plane being substantially parallel to said seat at a stage during the time said lever is rocking on the first pair of fulcrum edges, and the other pair of said fulcrum edges being disposed at a greater distance from said spherical center.

l0. In a fluid trap having a housing defining a liquid and vapor receiving chamber, an inlet opening at the bottom of the chamber, an outlet oriiice, a valve element for opening and closing the outlet oriiice, a lever for moving said valve element, and a float of the inverted bucket type suspended from said lever` over said inlet opening for actuating said lever to open and close the outlet orice, the combination therewith of a variable vent and connector mechanism for suspending the bucket from the lever, said mechanism comprising a vertically disposed stem pivotally connected at its upper end to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture, and a spring associated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket, the stiffness of said spring being selected to hold the intermediate portion of said stem downwardly against the top of the bucket under conditions of maximum buoyancy of the bucket and to yield against a force less than that required to move the lever in an orifice opening direction.

11. The improvement according to claim 10 in which said spring is disposed inside said bucket and engages the stem therein.

12. The improvement according to claim 10 in which said spring is mounted on said stem inside the bucket and engages the inner surface of the bucket.

13. The improvement according to claim 10 in which said spring is a leaf spring mounted at its center on said stem inside the bucket, said spring being shaped to bear upwardly at its opposite ends against the inside of the bucket and downwardly at its center against its connection with said stem.

14. A fluid trap according to claim 1 in which the fulcrum axis about which the lever arm rst rocks during movement of the valve element away from its seat is disposed in a diametric plane of the spherical surface of the valve element, said plane being substantially parallel to said seat at a stage during rotation of said lever about said axis.

15. A iiuid trap according to claim l in which the fulcrum axis about which the lever arm iirst rocks during movement of the valve element away from its seat is disposed in a diametric plane of the spherical surface of the valve element, said plane being substantially parallel to said seat at a stage during rotation of said lever about said axis,'and in which said axis is disposed at a distance from the spherical center of said surface less than its radius of curvature.

16. A uid trap according to claim 1 in which said power means is a oat of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem pivotally connected at its upper end to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture,

and a spring associated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket, the stiffness of said spring being selected to hold the intermediate portion of said stem downwardly against the top of the bucket under conditions of maximum buoyancy of the bucket and to yield against a force less than that required to move the lever in an oriiice opening direction.

17. A iiuid trap according to claim 1 in which said power means is a float of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem carrying the weight of the bucket, said stem being pivotally connected at its upper end to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture, and a spring associated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket, the stiffness of said spring being selected to hold the intermediate portion of said stem downwardly against the top of the bucket under conditions of maximum buoyancy of the bucket and to yield against a force less than that required to move the lever in an orice opening direction, said spring being mounted on said stem inside the bucket for engaging the inner surface of the bucket.

18. A fluid trap according to claim 1 in which said power means is a float of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem pivotally connected at its upper end to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture, and yieldable means associated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket under conditions of maximum buoyancy of the bucket and to yield against a force less than that required to move the lever in an oriiice opening direction, said yieldable means comprising a leaf spring mounted at its center on said stem inside the bucket, said spring being shaped to bear upwardly at its opposite ends against the inside of the bucket and downwardly at its center against its connection with said stem.

19. A iiuid trap according to claim 5 in which said power means is a iioat of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertical-ly disposed stem .pivotally connected at its upper lenc to the lever and having its lower fend projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an 'enlarged intermediate 'portion adapted to seat. ldowmvardly against the top oi the bucket and completely close 'said aperture, and a spring associated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket, the stiffness of said spring being selected to hold the intermediate portion of Isaid stem downwardly against the top of the bucket under conditions of maximum buoyancy oi the bucket and to yield against a force less than that 1requ'ired to move the lever in an `oriilce opening direction.

20. A uid trap. according to claim 5 in which said power means is a iloat of the inverte-d bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem carrying the weight of the bucket, said stem being pivotally connected at its upper end to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture, and a spring asn sociated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket, the stiffness of said spring being selected to hold the intermediate portion of said stem downwardly against the top of the bucketl under conditions of maximum buoyancy of the bucket and to yield against a force less than that required to move the lever in an orifice opening direction, said spring being mounted on said stem inside the bucket for engaging the inner surface of the bucket.

2l. A fluid trap according to claim 5 in which said power means is a float of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stern pivotally connected at its upper end to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top oi the bucket and completelyv close said aperture, and yieldable means associated therewith for urging the intermediate portion of stem downwardly against the top of the bucket, said yieldable means being selecterl to hold the intermediate portion of said stem downwardly against the top oi the bucket under conditions ci maximum buoyancy oi the bucket and to yield against a 'force less than that required to move the lever in an oriiice opening direction, said yieldable means comprising a leaf spring mounted at its center on said stem inside the bucket, said spring being shaped. to bear upwardly at its opposite ends against the inside of the bucket and downwardly at its center against its connection with said stern.

22. A fluid trap according to claim 1 in which the iulcrum about which the lever arm iirst rocks during movement of the 4valve clement away from its seat is disposed in a diametric plane of the spherical surface of the valve element, said plane being substantially parallel to said seat at a stage during rotation of lever about said axis, and in which said power means is a float o'f the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem pivotally connected at its upper end to the lever and having its lower end projecting with sulostantial clearance through an aperture centrally 'disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to s'eat downwardly against the top of the bucket and completely close said aperture, and a 'spring a'ssociated therewith for urging the intermediate portion of said stem downwardly 'against the top of the bucket, the stiness of said spring being 'selected to hold the intermediate portion of sai-d stem downwardly against the top of the bucket under conditions of' maximum buoyancy of the bucket and to yield 'against a 'force less than that required to move the lever in an orice opening direction.

23. A. huid 'trap according to claim l in which the fulcrum axis about which the lever arm rst rocks during movement of the valve element away from its seat is disposed in a diametric plane of the spherical surface of the valve element, said plane being substantially parallel to said seat at a stage during rotation of said lever about said axis, and in which said power means is a iloat of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem carrying the weight of the bucket, said stem being pivotally connected at its upper end. to the lever and having its lower end projecting with substantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture, and a spring associated therewith for urging the intermediate portion of said stem downwardly against the top oi the bucket, the stiffness of said spring being selected to hold the intermediate portion oi said stem downwardly against the topof the bucket under conditions of maximum buoyancy of the bucket and to yield against a force less than that required to move the lever in an orifice opening direction, said spring being mounted on said stem inside the bucket for engaging the inner surface of the bucket.

2li. A fluid trap according to claim 1 in which the iulcrum axis about which the lever arm first rocks during movement of the valve element away from its seat is disposed in a diametric plane of the spherical surface of the valve element, said plane being substantially parallel to said seat at a stage during rotation of said lever about said axis, and in which said power means is a float of the inverted bucket type suspended from said lever by a variable vent and connector mechanism comprising a vertically disposed stem pivotally connected at its upper end to the lever and having its lower end projecting with sub stantial clearance through an aperture centrally disposed in the top of the bucket, said stem including an enlarged intermediate portion adapted to seat downwardly against the top of the bucket and completely close said aperture, and yieldable means associated therewith for urging the intermediate portion of said stem downwardly against the top of the bucket, said yieldable means being selected to hold the intermediate portion of said stem downwardly against the top `of the bucket under conditions of maximum buoyancy of the bucket and to yield against Ia force less than that required to move the lever in an orifice opening direction, said yieldable means comprising a. leaf spring mounted at its center on said stern inside the bucket, said spring being shaped to bear upwardly at its opposite ends against the inside of the bucket and downwardly at its center against its connection with said stem.

25. The device of claim 1 including an abutment on the structure providing said stationary fulcrum elements disposed to engage said lever and limit its rocking movement in a valve closing direction when the valve element is in its ncrmal closed position.

26. The device of claim 1 in which the structure providing the pair of stationary fulcrum elements comprises a bifurcated bracket and the lever is mounted between the two spaced legs of the bracket, the two legs of said bracket having aligned apertures therethrough, each of said stationary fulcrum elements being defined by laligned portions of the edges of said apertures,

and said lever having trunnions extending laterally thereof in opposite directions into said apertures respectively and forming aligned portions of each of said rocking fulcrum elements for supporting the lever on said stationary fulcrum elements, the edges of said apertures yalso providing abutments disposed to engage said lever and limit its rocking movement in a valve closing direction when the valve element is in its normal closed position.

WILLIAM S. GOFF.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,901,833 Strong Mar. 14, 1933 1,988,127 Kuprva Jan. 15, 1935 2,004,953 Kaye June 18, 1935 2,053,641 Spade Sept. 8, 1936 2,232,583 Zies Feb. 18, 1941 

